Databases

Databases File This is a collection of records that gives a complete set of information about a certain topic. e.g. a class file would contain all the information about all the pupils in a class. Record This is the set of related information about one thing or individual e.g. one pupil from the file class. Field This contains a single piece of information eg surname, forename, teacher, subjects taken, register class, guidance teacher.

Features of Databases Add record At any time more information can be added to the database by adding records.  Create fields You can create the individual fields that make up the records in your database. Search on one field During a search the database is asked to find a particular item of information in one particular field. Sort on one field During a sort the records of a database are put into a certain order, e.g. alphabetically in order of surname or in ascending or descending order of height.

Features of Databases Alter record format This refers to the ability to change the structure of the fields of the database e.g. increase their length or adding new fields.  Search on more than one field It is often possible to search on more than one field e.g. a database of pupils in a school could be searched for the number of pupils in S3 who are studying Standard Grade Computing Studies. The two fields to be searched being year and subject.

Features of Database Computed field This is a field that contains a formula that calculates a value from other fields. Alter screen input format Some database packages allow the user to create a screen input form for the entry of new records, often so that these can mirror existing paper forms.   Alter output format This refers to the ability to define what the output is to be and in what form the output is going to be. That is the selection of all or some of the fields to be displayed or printed out. Also the format of the output i.e. list - tabular, graphical - charts or bar graphs. 

Features of Database Use of keywords Keywords are often used in information retrieval systems whereby items containing the given keyword are accessed by the computer and retrieved. In simpler systems only the titles of the stored items may be searched for the particular keyword though with some systems every word in the database can be checked.  Sort on more than one field Similar to the sorting with the Sports Table Spreadsheet task. A database could first sort a league table on points, then goal difference and then Goals Scored.